Den 11-06-2019 kl. 20:40, skrev Greg Kroah-Hartman:
On Tue, Jun 11, 2019 at 07:33:16PM +0200, Daniel Vetter wrote:
On Tue, Jun 11, 2019 at 5:37 PM Greg Kroah-Hartman gregkh@linuxfoundation.org wrote:
On Tue, Jun 11, 2019 at 03:56:35PM +0200, Sven Joachim wrote:
Commit 1e07d63749 ("drm/nouveau: add kconfig option to turn off nouveau legacy contexts. (v3)") has caused a build failure for me when I actually tried that option (CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT=n):
,---- | Kernel: arch/x86/boot/bzImage is ready (#1) | Building modules, stage 2. | MODPOST 290 modules | ERROR: "drm_legacy_mmap" [drivers/gpu/drm/nouveau/nouveau.ko] undefined! | scripts/Makefile.modpost:91: recipe for target '__modpost' failed `----
Calling drm_legacy_mmap is definitely not a great idea. I think either we need a custom patch to remove that out on older kernels, or maybe even #ifdef if you want to be super paranoid about breaking stuff ...
Upstream does not have that problem, as commit bed2dd8421 ("drm/ttm: Quick-test mmap offset in ttm_bo_mmap()") has removed the use of drm_legacy_mmap from nouveau_ttm.c. Unfortunately that commit does not apply in 5.1.9.
Most likely 4.19.50 and 4.14.125 are also affected, I haven't tested them yet.
They probably are.
Should I just revert this patch in the stable tree, or add some other patch (like the one pointed out here, which seems an odd patch for stable...)
... or backport the above patch, that should be save to do too. Not sure what stable folks prefer?
The above patch does not apply to all of the stable branches, so how about I just revert this? People can live with this option not able to turn off for now, and if they really want it, they can use a newer kernel, right?
Or add the simple fix suggested by Daniel (if I understand correctly):
From: Thomas Backlund tmb@mageia.org
Setting CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT=n (added by commit: b30a43ac7132) causes the build to fail with:
ERROR: "drm_legacy_mmap" [drivers/gpu/drm/nouveau/nouveau.ko] undefined!
Fix that by adding check for CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT around the code using drm_legacy_mmap()
Fixes: b30a43ac7132 drm/nouveau: add kconfig option to turn off nouveau legacy contexts. (v3) Signed-off-by: Thomas Backlund tmb@mageia.org
--- drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c +++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c @@ -168,8 +168,10 @@ nouveau_ttm_mmap(struct file *filp, stru struct drm_file *file_priv = filp->private_data; struct nouveau_drm *drm = nouveau_drm(file_priv->minor->dev);
+#if defined(CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT) if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET)) return drm_legacy_mmap(filp, vma); +#endif
return ttm_bo_mmap(filp, vma, &drm->ttm.bdev); }